AuthorTopic: Neumann U48 (Read 27403 times)

First:Congratulations! ou seem to have an all-stock U48 amplifier with the original, 'M' stamped, VF14!

You can identify the BV8 (A of B) by looking on the top of the transformer, closest to the tube (you may have to push the tube out of the way for this): you will find a piece of ID paper glued to the isolation wrapping on the transformer which contains the transformer number you have.

The visible, outermost secondary windings on the transformer is another clue: the "B" version has very thick wire, compared to the older "A" version.

Klaus, excuse my insistence, but where is the "M" stamped?I must say that I really love the sound of my U48, it killed my UM900, my E47c, my Pearlman and my M147 on vocals, I don't know if I want to keep it original and instead get an U47, I'm so tired of this VF14 thing, I trying to find one or two vf14 as spare, but it's not easy, right now I'm getting a beautiful Fairchild 670 from VK, but I'm worried about those hard to find 6386.

Thanks Klauss for all your info, I guess that even if I buy an original U47, I'm gonna modify my U48, so what is the next step?

Is that possible that my technicians make the mod? I have great engineers that bring service to all my gear, if it's easy, maybe they can perform the mod.Also, is there some kind of diagram of the U48 in order to know what to do on the mic?

One caution - you love the sound of your stock U48 and it is not assured that you will like the modded version better. Given the rare, all-original, pristine condition of the mic, and that it is functioning beautifully, there may be wisdom in leaving well enough alone.

Alan

Logged

“A working class hero is something to be,Keep you doped with religion and sex and T.V.”John Lennon

"Large signals can actually be counterproductive. If I scream at you over the phone, you don’t hear me better. If I shine a bright light in your eyes, you don’t see better.”Dr. C.T. Rubin, biomechanical engineer

Alan, thanks for your comments, you are right, I'm starting a collection, so I'm gonna leave my 48 as stock because mine is in a great condition and it's a shame made a modification if I can get an U47.I'm gonna get an U47 soon, I'm looking for a good one, Mike Nehra is finding me one Long body.

Yesterday I tried to buy one short body, but at first look, the mic looks doesn't look original at all, so I'm gonna wait for the "good" one.

They say the heart of Rock & Roll is still beating, which is amazing if you consider all the blow it's done over the years.

"The Internet enables pompous blowhards to interact with other pompous blowhards in a big circle jerk of pomposity." - Bill Maher

"The negative aspects of this business, not only will continue to prevail, but will continue to accelerate in madness. Conditions aren't going to get better, because the economics of rock and roll are getting closer and closer to the economics of Big Business America." - Bill Graham

of course, modifying a perfectly working U48 would never come to my mind, unless I had a perfectly obvious reason for doing so. A conversion from 47V to 60V gives you 2dB higher sensitivity, 2dB lower equivalent noise, and 2 dB less headroom. 2dB is usually not a good reason for a major modification of vintage mics.

Some further notes:

A one sided figure-8 characteristic is commonly called hypercardioid or supercardioid.

The "infamous BV8 version" is presumably the BV8B version, with 50 ohms output impedance. Specially made for the then requirements of the U.S. market and the then available pre-amps. I never knew it was so infamous, but if that's your opinion... It's just one of 4 transformer versions that were used in the U47 / 48, that could be set to 6 (or was it 7?) different possibilities.

The "infamous BV8 version" is presumably the BV8B version, with 50 ohms output impedance. ... It's just one of 4 transformer versions that were used in the U47 / 48, that could be set to 6 (or was it 7?) different possibilities.

Unfortunately, if you have the BV8B in your stock U48, you are not only stuck with the aforementioned lower s/n and output of that model, but you also cannot undo, by changing to different taps, the additional 4-6dB lowered output from this special transformer's secondary windings- a permanent, unchangeable feature.

Personally I like the U47 with the big transformer the most and different sounding than the later short body having the smaller transformer and different resistors etc long body's build after 1951 where build with smaller transformers having less distortion in the low-end. Just had listened to my U48 with new VF14 and new K47 sounding stunning especially on figure 8 I would not change anything in a orig. mic like that, never! still like the Big transformer U47 the most it's more velvet and vet sounding bit less output but more sound very musical and good on all most everything it's the only real U47 model that makes music and af course the U48 is very musical and smooth on figure 8 as well very good combination... Neumann thanks so much! www.pucksound.nl

What a great and informative thread. I'd only like to add that I have both a U-47 and U-48 and I find the musical differences between them to be virtually interchangable. And I'm pretty sure that I must have the lower output transformer. (But now I can check!)

I've often been encouraged by mythologizers to convert the 48 into the "superior" 47, but why would I want to give up the ability to do M/S recording with such a lovely colored pair of mics? As a vocal mic, tracking the same singer with either leads to an identical sound. The variations in a voice from day-to-day outweigh the minute differences between the mics.

Wow, what an awesome thread! So good as a matter of fact, that I just registered on PSW so I could thank you all for this wealth of information and also ask for all of your opinions on something.

I purchased a new (not vintage) TELEFUNKEN ELA M 251E for a good friend of mine when I set up her recording studio a few years ago. She's VERY happy with her 251, but she's now ready to add a U47 or U48 to her collection and I was planning on taking the same route, that is, to purchase a new (not vintage) TELEFUNKEN U47 or U48.

Just to be clear, this mic is intended for practical use, not collectibility... so variance in sound quality is the only concern... and I am aware of the internal differences between the vintage VF14M and the new VF14K tubes.

Any feedback would be most appreciated. By the way... I'm a vintage freak myself, so don't hold back ;^)Thanks!